The original post in this thread goes back almost a year. I bought the lens shortly after this post appeared, and after using the lens almost a year now myself I can second the original poster's observations. Very good image quality, and the lens is small, light, and easy to handle and use. I've really found the lens delightful to use, and as a result it spends more time on my camera than I anticipated when I got it.
In some ways the 70-300VR is a better lens, but in others the 55-300 has an advantage (smaller, lighter, greater zoom range). From what I can tell, the image quality of the two lenses is about the same. My thinking is that for a DX camera the advantages of the 55-300 outweigh the disadvantages.
Edited to add: With regard to the two questions above, you do have to switch to MF to manually focus the lens (one advantage the 70-300 has), and VR is very effective on this lens.